Quite a number of different machines have heretofore been employed for the purpose of delining the masonry or refractory inner wall of a blast furnace and the subject invention is considered to constitute improvements over the equipment or machines disclosed in various patents, such as for example, J. Armstrong U.S. Pat. No. 3,436,120 dated Apr. 1, 1969 which, among other things, discloses a platform which is held in the center of a furnace throughout the entire tear-down operation; D. R. Stauffer, U.S. Pat. No. 3,446,292 dated May 27, 1969, which shows a rig or platform held by outriggers engaging a furnace wall and tool structure carried and supported below the platform; and L. Skendrovic, U.S. Pat. No. 3,370,888 dated Feb. 27, 1968 which is similar to the aforesaid Stauffer Patent in that a tool structure is mounted below a support substantially on a vertical axis and carries complicated radially movable outriggers which abut the wall of a furnace and appear to continually maintain the machine centered on such axis.
In addition to the above, some machines used in the past require periodic adjustment of cables from the top of the furnace by a crew of men to lower the machine to many positions in the furnace as the liner therein is removed, as distinguished from the subject invention which, among other things, allows an operator on the machine to control such procedure, thereby materially affording a reduction in manpower.
The improvements constituting the subject invention or inventions will readily become apparent after the following OBJECTIVES AND DESCRIPTION are considered as hereinafter set forth.